Friends of the McCanns faced fresh allegations yesterday after it was claimed that sniffer dogs had found the "scent of death" on one of them.
The same police dog which reacted to Mrs McCann's clothes - first causing suspicion to fall on her - was alleged to have smelled "death" on one of the friends who had dinner with the couple the night Madeleine vanished.
Police sources briefed a Portuguese newspaper that two police dogs from South Yorkshire, trained to detect corpses, human remains and microscopic traces of blood, had reacted to some items of clothing.
Family spokesman Clarence Mitchell denied categorically that any such procedure had happened.
The newspaper did not reveal which of the friends' clothing was meant to have triggered the reaction. Police in South Yorkshire refused to comment.
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Clockwise from top left, Fiona Payne, Jane Tanner, Russell O' Brien, Rachael Oldfield
Read more...Detectives are writing to British police asking them to re-interview the seven friends the McCanns dined with on the night Madeleine vanished.
Madeleine's parents were dining in a tapas restaurant just yards from the apartment in the Mark Warner Resort in the Algarve, Portugal, when their daughter disappeared.
She had been sleeping inside the apartment with her brother and sister, twins Sean and Amelie.
According to reports from Portugal, all of those dining with the McCanns that night face further police questioning because their accounts of the night's events allegedly clashed.
Leicestershire police have consistently refused to comment on its role in the investigation and directed all questions to Portugal.
A spokeswoman said: "As the inquiry into the disappearance of Madeleine McCann is a Portuguese police investigation it is not appropriate for us to comment on it. Our role is to assist the Portuguese authorities, when and if they request it, with UK based inquiries.
"But because it is a Portuguese investigation, and because of the judicial system there, we are not able to disclose the nature of those inquires."
The seven friends - who, with the McCanns, make up the Tapas Nine - have been steadfast in their loyalty to Madeleine's family.
The group - most of them doctors and professionals - was made up of:
Still missing: Madeleine McCannDr Russell O'Brien, 36
A consultant in acute medicine at the Royal Devon and Exeter Hospital, he knew Gerry McCann from Leicester.
He was on holiday with his partner Jane Tanner and their two young daughters.
At 9.25pm he left the restaurant for around 25 minutes to check on one of the girls, who was ill.
He has been subject to a vicious Portuguese press campaign alleging he was absent for over an hour when Madeleine went missing. He has threatened to sue, insisting: "These reports are completely untrue and extremely hurtful."
Jane Tanner, 37
Dr O'Brien's partner. She arrived late at the tapas bar after treating their sick daughter.
On the way, she passed the McCanns' apartment and saw a man carrying a child. Crucially, her description of the child's clothes matched Madeleine's pink pyjamas.
Dr Matthew Oldfield, 37
Dr Oldfield, an endocrinologist at Kingston Hospital in South-West London, went to check the McCann children at 9 25pm.
But he did not look inside the flat - simply listened from outside to ensure Madeleine and the twins were not crying.
Rachael Oldfield, 36
Dr Oldfield's wife, a former lawyer who is now a recruitment consultant.
She is one of four witnesses who claim to have seen the first suspect, British expat Robert Murat, near the McCanns' flat.
Last month she angrily dismissed reports that police had intercepted phone calls and emails between the McCanns and their friends which contradicted the group's earlier statements.
Mrs Oldfield accused Portuguese police of "throwing mud when we are not able to defend oursleves"
David Payne, 41
Mr Payne is a senior research fellow in cardiovascular sciences at Leicester University
He and his wife and mother-in-law joined the group at 8.55pm.
They are believed to have been the only ones using a baby monitor to check on their two children.
Mr Payne has said: "All these smears and rumours are overshadowing the important thing, which is to get Madeleine back."
Dr Fiona Payne, 34
Mr Payne's wife, she is understood to have told police she saw Mr Murat shortly after Madeleine vanished.
Dr Payne and her husband stayed on in the Algarve to support the McCanns. When the couple were made official suspects, she said: "It's an outrage - a preposterous accusation."
Dr Payne's mother. She has given no public interviews.
Read more: http://www.dailymail.co.uk/news/article-483881/Madeleine-Sniffer-dogs-scent-death-McCanns-friends.html#ixzz13pGnxbJr